Vegetation dynamics based on NDVI in Yangtze River Basin (China) during 1982-2015

Abstract

Knowledge of vegetation dynamics is important for the sustainability of natural resources and understanding the changes in ecosystems and its impact to earth’s environment. We have carried out analysis of GIMMS (Global inventory modelling and mapping studies) NDVI3g (third generation normalized difference vegetation data for the period 1982-2015. Based on the Linear Regression (LR) analysis, the Mann-Kendall (MK) test with Sen’s slope estimator and Kriging interpolation method, we have investigated the spatiotemporal variations of vegetation NDVI in the Yangtze River Basin (YRB). The results show pronounced increase in the annual mean NDVI at the rate of 0.01/10yr during 1982-2015, with significant turning point (TP) around 1994. The spatial distribution of the annual mean NDVI reasonably increased in the northern, eastern and south-western YRB, while decreased in the Yangtze River Delta (YRD) and parts of the southern YRB during 1982-2015. Pronounced change in NDVI trend is found in different seasons, for example, the increasing trend during spring (0.02/10yr) and in autumn (0.02/10yr) was higher compared to winter (0.006/10yr) and summer (0.002/10yr) seasons.